A telecommunication service such as a call service or a charging service has an extremely high requirement for reliability, which reaches five 9s (99.999%), and is far greater than enterprise-level reliability. According to materials that are currently disclosed, reliability of a cloud computing system is about 95% to 98%, which is far less than a reliability requirement of a telecommunication service. However, as cloudification is a megatrend, how to continue keeping telecommunication-level reliability of a telecommunication service after migrating the telecommunication service to cloud is a technical problem that needs to be resolved.
For a software service, an important means for improving reliability is a two-node cluster in hot standby mode. The prior art provides a dual-server cloudification solution. According to the solution, dual servers (for example, an active server and a standby server) are separately deployed on a cloud end. The active server executes an external request and performs synchronization with the standby server after executing the external request. A synchronization process includes data synchronization and status synchronization.
However, in the dual-server cloudification solution provided in the prior art, dual-server standby reliability reduces when a volume of data requiring synchronization is relatively great, resulting in an obvious delay of dual-server switch, and further reducing service reliability.